SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '39905726ea7320934dd69f84746657a3e184c4dfa928f2b9601d0e32194309b5' 
  AND token = 'cCl4togJGU8usdO9tL++JkVZsQJwBbkvUFM1Pknc6PQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}